Neutron Lifetime Anomaly and Big Bang Nucleosynthesis

We calculate the Big Bang Nucleosynthesis abundances for helium-4 and deuterium for a range of neutron lifetimes, ${\tau }_n=840-1050$ s, using the state-of-the-art Python package $\text{textsc}PRyMordial$. We show the results for two different nuclear reaction rates, calculated by NACRE II [1] and the PRIMAT [2] collaborations.